It´s hilarious that the OP is being called a troll by a bunch of people who have absolutely no idea about how it works.

There are 4 stat changing buffs from Mystic Chests.
All of them can be in use simultaneously, in addition, you can have one (1) cooking buff running at any given point for a total of 5 buffs.
They are confirmed to work in WvW, and as of BWE3 the flavor text has been changed from "does not work in PvP" to "does not work in structured PvP".
Whales, for whom items like these are intended, coming from f2p games will absolutely love them, by getting their fix from the RNG and the buffs themselves; a constant speed buff in WvW is incredibly strong whether you think it is or not.

the armor is awesome...if you don't mind what level and how did you acquire so i can get an idea of when / how my sylvari will be wearing racial armor?

Thanks! And I agree, the armor is really awesome and I set up a goal to get it before the end of this last BWE

The armor is ... [heavy] Thicket armor (if I remember it correctly), and you can get it at level 35 from an NPC in the Grove. When you look on the map in the Grove, you will notice 3 NPCs standing in a triangle shape - one of them has this armor on offer at a price of 1 gold per piece.